This chemistry question involves key chemical concepts and calculations. The detailed solution below walks through each step, from identifying the reaction type to computing the final answer.
ScanSolve AI Answer
You're on a roll — here's the solution for question 3: Question 3: How many chloride ions are present in 1.7 g of magnesium chloride crystals? (Avogadro's constant = 6.0 × 10^23, Mg = 24, Cl = 35.5) Step 1: Determine the chemical formula of magnesium chloride. Magnesium is a Group 2 element, forming Mg^2+ ions. Chlorine is a Group 17 element, forming Cl^- ions. To balance the charges, the formula for magnesium chloride is MgCl_2. Step 2: Calculate the molar mass of magnesium chloride (MgCl_2). Given atomic masses: Mg = 24, Cl = 35.5 Molar mass of MgCl_2 = Molar mass of Mg + (2 × Molar mass of Cl) Molar mass of MgCl_2 = 24 g/mol + (2 × 35.5 g/mol) Molar mass of MgCl_2 = 24 g/mol + 71 g/mol = 95 g/mol Step 3: Calculate the moles of magnesium chloride in 1.7 g. Given mass of MgCl_2 = 1.7 g Moles of MgCl_2 = MassMolar mass Moles of MgCl_2 = 1.7 g95 g/mol ≈ 0.01789 mol Step 4: Calculate the number of MgCl_2 formula units. Using Avogadro's constant (6.0 × 10^23 formula units/mol): Number of MgCl_2 units = Moles × Avogadro's constant Number of MgCl_2 units = 0.01789 mol × 6.0 × 10^23 units/mol Number of MgCl_2 units ≈ 0.10734 × 10^23 = 1.0734 × 10^22 units Step 5: Calculate the number of chloride ions. From the formula MgCl_2, each formula unit contains 2 chloride ions (Cl^-). Number of Cl^- ions = 2 × Number of MgCl_2 units Number of Cl^- ions = 2 × 1.0734 × 10^22 Number of Cl^- ions = 2.1468 × 10^22 Rounding to two significant figures (due to 1.7 g), we get: Number of Cl^- ions = 2.1 × 10^22 The number of chloride ions present is 2.1 × 10^22. What's next? Send 'em.